1. Field of the Invention
The present invention relates to a human face detection and tracking device, and more particularly to a human face detection and tracking device capable of generating an updated skin color threshold value.
2. Related Art
At present, image capturing devices have been widely applied in daily life. The image capturing device uses an optical sensor to capture an image, and converts the image into digital signals, and the digital signals can be stored. Through the digital signals captured by the image capturing device in combination with digital image processing technologies, various applications can be designed.
Among images captured by image capturing devices, portraits are the core. For example, currently, many image capturing devices are provided with human face detection and human face tracking technologies, which can assist in automatic multi-focusing of the shot region. In addition, the human face detection technology can be also used to determine whether a person is present in a particular region, for example, the human face detection technology can be applied to determine whether there is a user viewing a television screen in front of the television screen. When it is determined by using the human face detection technology that no person is in front of the television screen, the television screen may be automatically turned off, thereby achieving the effect of energy saving.
Human face detection is to determine whether an object being shot is a human face by analyzing and comparing visual feature information of the human face. However, in fact, the appearance of the human face is not steady, because people can make many facial expressions by controlling facial muscles. Besides, the human face looks quite different from different angles. In addition, human face detection is also susceptible to light conditions (for example, day and night, indoor and outdoor or special light), which increases the possibility of false determinations.